Sulfite-Driven, Oxorhenium-Catalyzed Deoxydehydration of Glycols
Sulfite-Driven, Oxorhenium-Catalyzed Deoxydehydration of Glycols
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DOI：
10.1021/om2001662
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发表时间：
2011-05-23
期刊：
影响因子：
2.8
通讯作者：
Nicholas, Kenneth M.
中科院分区：
文献类型：
--
作者：
Ahmad, Irshad;Chapman, Garry;Nicholas, Kenneth M.
甲基三氧化铼和过氧化铼盐催化亚硫酸盐使二醇脱氧脱水（DODH），区域特异性地产生烯烃。研究了这些反应与多元醇底物、还原剂、催化剂、溶剂和各种添加剂有关的范围和效率。一般来说，MeReO（3）是亚硫酸盐驱动的DODH的更活性的催化剂，但是Z（+）ReO（4）（-）衍生物（Z = Na，Bu（4）N）更有选择性。环氧化物也能被Na（2）SO（3）/MeReO（3）脱氧，但不能被Bu（4）NReO（4）脱氧。过氧化氢酸盐催化剂还促进乙二醇DODH与其它还原剂，PR（3）、仲醇和ArSMe。1，2-环己二醇与（+）-酒石酸二乙酯的DODH反应具有很高的顺式立体选择性。多元醇内消旋体大部分转化为1，3-丁二烯以及少量的2-丁烯-1，4-二醇和2，5-二氢呋喃，表明更快的末端二醇DODH。化学计量反应研究证明了一种催化途径的可行性，该途径包括：（a）乙二醇与MeReO（3）缩合形成MeRe（VII）O（2）（乙醇酸盐）;（B）Re（VII）-乙醇酸盐通过亚硫酸盐或PR（3）进行O-转移还原，生成[MeRe（v）O（乙醇酸盐）]（2）;以及（c）还原的Re-乙醇酸盐热裂解，生成烯烃（以及MeReO（3）的再生）。
Methyltrioxorhenium and perrhennate salts catalyze the deoxydehydration (DODH) of glycols by sulfite, producing olefins regiospecifically. The scope and efficiency of these reactions with respect to the polyol substrate, reducing agent, catalyst, solvents, and various additives are investigated. In general, MeReO(3) is a more active catalyst for sulfite-driven DODH, but the Z(+)ReO(4)(-) derivatives (Z = Na, Bu(4)N) are more selective. Epoxides are also deoxygenated by Na(2)SO(3)/MeReO(3), but not by Bu(4)NReO(4). The perrhenate catalysts also promote glycol DODH with other reductants, e.g., PR(3), secondary alcohols, and ArSMe. The DODH reactions of 1,2-cyclohexanediol and (+)-diethyl tartrate occur with high syn-stereoselectivity. The polyol meso-erythritol is largely converted to 1,3-butadiene with minor amounts of 2-butene-1,4-diol and 2,5-dihydrofuran, indicating faster terminal glycol DODH. Stoichiometric reaction studies demonstrate the viability of a catalytic pathway involving (a) glycol condensation with MeReO(3) to form MeRe(VII)O(2)(glycolate); (b) O-transfer reduction of the Re(VII)-glycolate by sulfite or PR(3) to produce [MeRe(v)O(glycolate)](2); and (c) thermal fragmentation of the reduced Re-glycolates to produce olefin (and regeneration of MeReO(3)).